ZFS allows, by default, sharing of spare devices among different pools;
this commit simply restores this functionality for disk devices and
adds an additional tests case to the ZFS Test Suite to prevent future
regression.
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: loli10K <ezomori.nozomu@gmail.com>
Closes#7999
2e55034471